This specification relates to data processing and content distribution.
The Internet provides access to a wide variety of resources, such as image files, audio files, video files, and web pages. A search system can select one or more resources in response to receiving a search query. A search query is data that a user submits to a search system to obtain search results for resources in an effort to satisfy the user's informational needs. The search queries can be received in the form of text input, e.g., one or more query terms or in the form of image input, audio input, or other types of input. The search system can select and score resources based on their relevance to the search query and/or on their importance relative to other resources to provide search results that link to the selected resources. The search results are typically ordered according to the scores and presented according to their order.
In addition to search results, an advertising system (or another content distribution system) may provide advertisements (or other content items) that are responsive to the query. For example, the search query may be used to identify an advertisement using a keyword that matches the search query. In turn, the identified advertisement can be provided for presentation with the search results.
Search systems can provide query suggestions to users to help users obtain resources that satisfy their informational needs. As used herein, the term “query suggestion” is a suggested query that can be used to refine a search query that has been input by the user. Some search systems provide query suggestions for a partial query, which can be in the form of a list that can be populated prior to the query input being completed. To facilitate delivery of query suggestions for partial query, a client can send suggestion requests to a search system with each keystroke, and the search system can provide query suggestions having prefixes that match the entered characters. Once received, the client device displays these suggestions for user selection.